System and method for planning support removal in hybrid manufacturing with the aid of a digital computer

Abstract

Parameters of a set of tools are stored on a storage device. The tools are part of a manufacturing assembly usable for removing one or more support structures from a part. The support structures are formed with the part to facilitate additive manufacturing of the part. A near-net shape is modeled which includes the part combined with the support structures. A process plan is developed that includes subtractive manufacturing operations by the manufacturing assembly that remove the support structures. The process plan repeatedly updates the near-net shape as each one of the support structures is incrementally removed.

What is claimed is: 
     
       1. A method comprising:
 storing parameters of a set of tools of a manufacturing assembly usable for removing one or more support structures from a part, the support structures formed with the part to facilitate additive manufacturing of the part; 
 modeling a near-net shape comprising the part combined with the support structures; and 
 developing a process plan comprising subtractive manufacturing operations by the manufacturing assembly that remove the support structures, wherein the process plan repeatedly updates the near-net shape as each one of the support structures is incrementally removed. 
 
     
     
       2. The method of  claim 1 , wherein the process plan removes only those parts of the support structures that are in contact with the part. 
     
     
       3. The method of  claim 1 , wherein developing the process plan comprises:
 representing a set of states, each state identifying an orientation of the manufacturing assembly and describing the near-net shape with selected ones of the support structures that remain at the state, with one of the states representing an initial state; 
 representing a set of actions, each action describing one of the orientations of the manufacturing assembly and describing removal of at least one of the support structures from the near-net shape; 
 starting at the initial state, repetitively transitioning from one of the states to another of the states by choosing one of the actions as guided by a cost constraint function until a goal condition is satisfied; and 
 using the chosen actions to form the process plan. 
 
     
     
       4. The method of  claim 3 , wherein each of the orientations of the set of states is selected from a limited set of total orientations, the limited set of total orientations reducing a deviation of the tools from a surface normal of the part. 
     
     
       5. The method of  claim 4 , wherein the reducing the deviation of the tools from the surface normal of the part minimizes scalloping of the part. 
     
     
       6. The method of  claim 1 , wherein a greedy algorithm is used to plan the incremental removal of the support structures from the near-net shape. 
     
     
       7. A system comprising:
 a storage device that stores a model of a part and parameters of a set of tools of a manufacturing assembly usable for removing one or more support structures from the part, the support structures formed with the part to facilitate additive manufacturing of the part; and 
 a processor and memory coupled to the storage device and operable to perform steps comprising: 
 modeling a near-net shape comprising the part combined with the support structures; and 
 developing a process plan comprising subtractive manufacturing operations by the manufacturing assembly that remove the support structures, wherein the process plan repeatedly updates the near-net shape as each one of the support structures is incrementally removed. 
 
     
     
       8. The system of  claim 7 , wherein the process plan removes only those parts of the support structures that are in contact with the part. 
     
     
       9. The system of  claim 7 , wherein developing the process plan comprises:
 representing a set of states, each state identifying an orientation of the manufacturing assembly and describing the near-net shape with selected ones of the support structures that remain at the state, with one of the states representing an initial state; 
 representing a set of actions, each action describing one of the orientations of the manufacturing assembly and describing removal of at least one of the support structures from the near-net shape; 
 starting at the initial state, repetitively transitioning from one of the states to another of the states by choosing one of the actions as guided by a cost constraint function until a goal condition is satisfied; and 
 using the chosen actions to form the process plan. 
 
     
     
       10. The system of  claim 9 , wherein each of the orientations of the set of states is selected from a limited set of total orientations, the limited set of total orientations reducing a deviation of the tools from a surface normal of the part. 
     
     
       11. The system of  claim 10 , wherein the reducing the deviation of the tools from the surface normal of the part minimizes scalloping of the part. 
     
     
       12. The system of  claim 7 , wherein a greedy algorithm is used to plan the incremental removal of the support structures from the near-net shape. 
     
     
       13. A method comprising:
 storing parameters of a machining tool assembly usable for removing one or more support structures from a part, the support structures formed with the part to facilitate additive manufacturing of the part; 
 representing a set of states, each state identifying an orientation of the machining tool assembly and describing a near-net shape comprising the part combined with selected ones of the support structures that remain at the state, with one of the states representing an initial state; 
 representing a set of actions, each action describing one of the orientations of the machining tool assembly and describing removal of at least one of the support structures from the near-net shape; 
 starting at the initial state, repetitively transitioning from one of the states to another of the states by choosing one of the actions as guided by a cost constraint function until a goal condition is satisfied; and 
 using the chosen actions to form a process plan comprising subtractive manufacturing operations used by the machining tool assembly to remove the support structures. 
 
     
     
       14. The method of  claim 13 , wherein each of the orientations of the set of states is selected from a limited set of total orientations, the limited set of total orientations reducing a deviation of the machining tool assembly from a surface normal of the part. 
     
     
       15. The method of  claim 14 , wherein the reducing the deviation of the machining tool assembly from the surface normal of the part minimizes scalloping of the part. 
     
     
       16. The method of  claim 13 , wherein the cost constraint function minimizes a time to perform to perform the operations by the machining tool assembly. 
     
     
       17. The method of  claim 13 , wherein the cost constraint function maximizes a surface finish of the part. 
     
     
       18. The method of  claim 13 , wherein choosing one of the actions as guided by the cost constraint function comprises using an A* algorithm. 
     
     
       19. The method of  claim 13 , wherein a greedy algorithm is used to plan the removal of the at least one of the support structures from the near-net shape. 
     
     
       20. The method of  claim 13 , wherein each action removes only those parts of the support structures that are in contact with the part.